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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14, c++17, c++20
// template<class G = E> constexpr E error_or(G&& e) const &;
// template<class G = E> constexpr E error_or(G&& e) &&;
#include <cassert>
#include <concepts>
#include <expected>
#include <type_traits>
#include <utility>
struct ConstructFromInt {
int value;
constexpr ConstructFromInt(int v) : value(v) {}
};
constexpr bool test_default_template_arg() {
// const &, has_value()
{
const std::expected<int, ConstructFromInt> e(5);
std::same_as<ConstructFromInt> decltype(auto) x = e.error_or(10);
assert(x.value == 10);
}
// const &, !has_value()
{
const std::expected<int, ConstructFromInt> e(std::unexpect, 5);
std::same_as<ConstructFromInt> decltype(auto) x = e.error_or(10);
assert(x.value == 5);
}
// &&, has_value()
{
const std::expected<int, ConstructFromInt> e(5);
std::same_as<ConstructFromInt> decltype(auto) x = std::move(e).error_or(10);
assert(x.value == 10);
}
// &&, !has_value()
{
const std::expected<int, ConstructFromInt> e(std::unexpect, 5);
std::same_as<ConstructFromInt> decltype(auto) x = std::move(e).error_or(10);
assert(x.value == 5);
}
return true;
}
constexpr bool test() {
// const &, has_value()
{
const std::expected<int, int> e(5);
std::same_as<int> decltype(auto) x = e.error_or(10);
assert(x == 10);
}
// const &, !has_value()
{
const std::expected<int, int> e(std::unexpect, 5);
std::same_as<int> decltype(auto) x = e.error_or(10);
assert(x == 5);
}
// &&, has_value()
{
std::expected<int, int> e(5);
std::same_as<int> decltype(auto) x = std::move(e).error_or(10);
assert(x == 10);
}
// &&, !has_value()
{
std::expected<int, int> e(std::unexpect, 5);
std::same_as<int> decltype(auto) x = std::move(e).error_or(10);
assert(x == 5);
}
return true;
}
int main(int, char**) {
test();
static_assert(test());
test_default_template_arg();
static_assert(test_default_template_arg());
return 0;
}
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